For his part, Dr. Rashad Ramkissoonprimary care physician Houston Methodistexplains that “caffeine works by blocking sleep-promoting receptors in the brain, called adenosine receptors» And adds: “It can do this because, structurally, caffeine is similar to adenosine, the molecule that normally binds to these receptors.”
One function of adenosine is to regulate the sleep/wake cycle. Its levels fluctuate in the brain: they are quite low when you wake up and gradually rise throughout the day until caffeine blocks adenosine receptors. When this happens, the pathways that promote sleep are not active.
how much caffeine is too much
Experts talk about healthy adults, according to Food and Drug Administration (FDA) scientists 400 mg a day – Four to five cups of coffee – an amount that is not generally associated with dangerous negative effects. However, there is wide variation in how sensitive people are to the effects of caffeine and how quickly they metabolize it.
How long does caffeine stay in the body?
Normally, FDA scientists say, the body can Takes 4 to 6 hours to metabolize half What was eaten? This means that up to six hours after drinking a cup of coffee or Coca-Cola, half of the caffeine consumed is still present in the body, keeping you alert. So drinking a cup of coffee at 4 pm after lunch can keep you awake when you go to bed at 10 pm.
sleep but sleep poorly
Another factor to take into account sleep quality, Dr Deirdre ConroyAn expert in sleep behavior at the University of Michigan, explains that caffeine also affects the quality of sleep, not just the ability to fall asleep. Doctors explain that “the properties of caffeine remain in the body for several hours, even when you do not feel its stimulating effect.” This means that even if you fall asleep, caffeine can still affect you. stages of sleep Without us realizing it. In this sense, the sleep expert is more restrictive with regard to hours and says: “In general, all products containing caffeine should be eliminated eight hours before sleep,